The Professional Plaza Tower, also known as the 'Hammer and Nail' building due to its two iconic illuminated signs (now removed), is a high-rise building located at 3800 Woodward Avenue in Midtown Detroit, Michigan. It was listed on the National Register of Historic Places in 2016. The Professional Plaza Tower was built as part of the ambitious Detroit Medical Center urban renewal plan carried out in the 1960s. The project, which envisioned a peripheral ring of residential and commercial buildings, including three neighboring twelve-story towers, surrounding the central hospital complex, was never fully realized; however the Professional Plaza Tower, constructed between 1964 and 1966 to house the offices of physicians, surgeons, and dentists, succeeded in bringing medical professionals back into the city, and rapidly established itself as an anchor to the Medical Center.
This project was a special historic restoration with over-site from the NPS. Our work consisted of all types of sealant replacement, precast concrete repairs, steel restoration and exterior coatings. One of the main challenges on this project was the sheer amount of sealant related material that was used over the years to fix leaks in what was one of the first curtain wall systems to be installed in the state of Michigan. After trying several methods to achieve a clean surface, we ending up using wire wheels on a six inch grinder. Each approach and method had to be arranged as a mock-up, with the Architect’s review on each and every step. Upon approval, we removed and replaced all sealants on the precast and curtain walls and coated the substrates. While we were performing the work, we noticed that the precast had moved over the years and was the reason why these spalls had occurred. The original anchoring detail was not adequate and was only going to cause this problem to recur. The major challenge with designing a proper long-term repair was to maintain the historic look of this building. The repairs were completed from the inside using threaded rods anchored to a steel plate through the panels, welded to the structural steel. With the collaboration of RAM Construction Services, the Construction Manager and Owner, we achieved our goals and the project was a success.